The present invention relates to a multiprocessor exchange provided with a floating function and, more particularly, to an exchange provided with a plurality of call control processors for executing a call processing on the basis of call control information, and further provided with a floating function, which is a function of executing a distributed call processing on a multiplicity of lines by allocating the lines to the respective call control processors logically through a maintenance procedure, that is, without changing the physical line connection.
In a conventional multiprocessor STM (Synchronous Transfer Mode) exchange which is not provided with a floating function, all of the lines (subscribers/trunks), the line control firmwares, the switches SW and the call control and signal control processors are physically connected.
FIG. 21 shows the structure of an example of such conventional multiprocessors having no floating function. In a conventional multiprocessors STM exchange, line information data 1a to 1c, for example, related to lines A to C, respectively, are held by a line control firmware LFM1 which accommodates the lines A to C, while call information data 2a to 2c related to the calls of the lines A to C, respectively, are held by a call control and signal control processor CSPR1 for controlling a switch SW1 which accommodates the lines A to C. Line information data 1d related to a line D is held by a line control firmware LFM2 which accommodates the line D, while call information data 2d related to the call of the line D is held by a call control and signal control processor CSPR2 for controlling a switch SW2 which accommodates the line D.
FIG. 22 is an explanatory view of the line information data 1axcx9c1d which are held by a line state memory 3 of each of the line firmwares LMF1 and LMF2. The line state memory stores the following seven pieces of information (1) to (7) on each line:
(1) task execution display for displaying whether or not the task of the call which has used the line is being executed;
(2) a state number for indicating the state (state for receiving a dial number, ringing state, talking state, etc.) of the line control firmware;
(3) a link data number which is a control number of a memory related to a line controlled by the firmware;
(4) flush monitor information for indicating whether or not the hook flushing of the subscriber is allowed;
(5) a line type for indicating the type (general subscriber, public telephone, party line telephone, etc.) of the line;
(6) a call type for discriminating between a general call and a test call; and
(7) relief information for indicating whether or not the line is to be relieved at the time of restart/trouble.
FIG. 23 is an explanatory view of the call information data 2axcx9c2d and the line related data 2axcx9c2dxe2x80x2 which are held by a call state memory 4 and a line related memory 5 of each of the call control and signal control processors CSPR1 and CSPR2. The call state memory 4 stores the following 9 pieces of information:
(1) control information for indicating whether or not the memory is being used;
(2) call state number given according to a calling stage (dialling, ringing, talking, etc.);
(3) control number for checking the call using the memory;
(4) line information which is general information on the line such as a subscriber and a trunk and which includes a subscriber number (phone number) and accommodated position information for indicating the position of a subscriber and a trunk in the exchange;
(5) translated information obtained by translating a given numeral (call type such as local call and international call, receivable number of figures, accounting information, etc.);
(6) numeral information received with respect to the call;
(7) time information on the exchange processing such as call time, response time, and call end time;
(8) timer information on the types of the timers started for processing the call (timer for measuring period of the ringing, timer for measuring period between the figures when receiving numbers, etc.) and
(9) traffic information on the call.
The line related memory 5 stores the following 4 pieces of information.:
(1) control information for indicating whether or not the memory is being used;
(2) line state number for indicating the state (vacant, used, troubled, etc) of the line;
(3) line information for indicating the position of the path in the exchange used by the line; and
(4) control number for checking the call using the memory.
In the above-described multiprocessor exchange, when there is a call in a stable communication state (stable call) between lines which are controlled by different processors and firmwares like a call between the line A and the line D, the xe2x80x9crestart processing with reliefxe2x80x9d executed by the processor CSPR1, which executes a call control and a signal control for the line A, will be described.
The stable call is a call in the course of talking or ringing. In general, the stable call is a call which does not incur contradiction in the data held by the call control processor and the line control firmware, even if the call processing is stopped and communication is continued or which can correct the contradiction if any. The xe2x80x9crestart processing with reliefxe2x80x9d is a processing executed by a relief/restart program when, for example, abnormality in a program or apparatus, access of illegal data, etc. are detected in a monitoring program. The restart processing is classified into 3 levels from a first to third levels. The xe2x80x9crestart processing with reliefxe2x80x9d is executed at a first level.
First level: only the processing in the course of execution is initialized and the call in a stable state is not initialized. When success is not obtained even after four cycles of restart processings at a first level, a restart processing at a second level is executed.
Second level: all the resources including hardwares are initialized, and a stable call is also initialized. When success is not obtained even after four cycles of restart processings at a second level, a restart processing at a third level is executed.
Third level: the file is reloaded from the main memory backup region of a hard disk HDU so as to initialize all the resources including hardwares.
When the processor CSPR1 is to execute a xe2x80x9crestart processing with reliefxe2x80x9d, the processor instructs the line control firmware LFM1 which accommodates the line A to stop the call control. The call control and signal control processor CSPR1 then executes a match processing on the internal data (call control information 2a of the line A), and after the end of the match processing, the processor sends relief information to the line control firmware LFM1 and requires a match processing. The call control and signal control processor CSPR1 executes a match processing again on the basis of the result of the match processing received from the firmware LFM1, and after the end of the match processing, it instructs the line control firmware LFM1 to start a call processing.
The general matching procedure is as follows.
(a) A processor (for example, the call control and signal control processor CSPR1) starts a xe2x80x9crestart processing with reliefxe2x80x9d.
(b) The processor requires all the subordinate firmwares (e.g., the line control firmware LFM1) to stop the call control. The firmware then stops the call control processing of all the subordinate lines. However, the call control information such as on-hook information, off-hook information sent from the lines is held.
(c) The processor executes the release (initialization) of the temporary data for call control which are in the process of production, on the calls except the stable call
(d) The processor informs all the subordinate firmwares of the relief imformation on the stable call which has been judged to be relieved.
(e) Each of the firmwares compares the line states of all the lines under its own control with the relief information received from the host processor, and releases or initializes the call related data on the lines which are not included in the relief information (initialization). Even if a line is included in the relief information (the processor recognizes the line as an object of relief, if a firmware judges the line is not an object of relief, the firmware informs the host processor of the line in non-relief information. For example, when the stable call in the course of talking is ended in the process of xe2x80x9crestart processing with reliefxe2x80x9d, the firmware judges the stable call not to be an object of relief and informs the host processor of the line which is not an object of relief in non-relief information.
(f) The processor receives the non-relief information from each firmware, and releases the related temporary data for call control.
(g) When the match processing in the exchange is finished, the processor requires each firmware to start a call control, and each firmware starts a call processing.
(h) In the case of a digital subscriber (BRI/PRI: Basic Rate Interface/Primary Rate Interface), since a subscriber has a call state, a message (Status-enq) in accordance with the advice is sent to the subscriber so as to execute the match processing for each subscriber.
The matching procedure of the xe2x80x9crestart processing with reliefxe2x80x9d executed by a-firmware is the same as the above-described procedure except for the way of start.
Although the above-described match processing is executed between the call control processor CSRP1 and the line control firmware LFM1, match processing is not executed between the line control firmware LFM2 which accommodates the line D and the the call control and signal control processor CSRP2. But when the match processing is finished between the call control processor CSRP1 which holds the information on the line A and the line control firmware LFM1, the stable call between the line A and the line D is relieved by the communication between the processors CSRP1 and CSRP2.
As described above, in a conventional multiprocessor exchange having no floating function, it is possible to relieve a stable call at the time of execution of the xe2x80x9crestart processing with reliefxe2x80x9d so long as the processors and the firmwares are physically connected even if a call is controlled by different processors and firmwares like a call between the lines A and the line D. More specifically, since all types of information on call control is held by processors and firmwares which are physically connected, it is possible to relieve state of a stable call by executing a match processing between these processors and firmwares which are physically connected at the time of executing the xe2x80x9crestart processing with reliefxe2x80x9d.
In the conventional multiprocessor exchange having no floating function shown in FIG. 21, there is a case in which it is favorable to shift a predetermined line, for example, the line C to another processor, for example, the call control and signal control processor CSRP2 or a new processor to lighten the load of the call control and signal control processor CSRP1. In such a shift, the physical connection of the line C is changed after the call on the line C is finished or the call is forcibly released in a maintenance procedure, and the line data (the type of the line, phone number information, service information, etc.) on the line C are eliminated from the call control processor CSPR1 and set again in the new call control processor CSPR2 to which the line C is shifted, in the maintenance procedure.
FIGS. 24 and 25 are explanatory views of examples of call connection and a shift of a line, respectively, in a multiprocessor exchange having no floating function. The same reference numerals are provided for the elements which are the same as those shown in FIG. 21. Line controllers LCT1 and LCT2 are provided with line control hardwares SHF1 and SHF2, respectively, and line control firmwares LFM1 and LFM2, respectively. The line control hardwares SHF1 and SHF2 execute time-division multiplex on the transmission signals sent from a plurality of lines and input the time-division multiplex signals into switches SW1 and SW2, respectively, through the highways HW1 and HW2, respectively, and separate the time-division multiplex signals input from the switches SW1 and SW2, respectively, through the highways HW1 and HW2, and sent the separated signals to the lines..
1) The line A is accommodated in the highway HW1, and the call control and signal control processor CSRP1 manages the line data. The line B is accommodated in the highway HW2, and the call control and signal control processor CSRP2 manages the line data (see FIG. 24).
2) The call control information between the line A and the call control and signal control processor CSRP1 is transmitted and received through the line A, the line control firmware LFM1 and the call control processor CSPR1, or by the reverse route. The call control information between the line B and the call control and signal control processor CSRP2 is transmitted and received through the line B, the line control firmware LFM2 and the call control processor CSPR2, or by the reverse route. The processors CSRP1 and CSRP2 transmit and receive call control information therebetween at the time of communication between the processors. Signals such as sound and voice are transferred from the line A to the line B through the line control hardware SHF1, the switch SW1, the switch SW2, and the line control hardware SHF2, or by the reverse route.
(3) If the call control and signal control processor CSRP2 assumes a high load state in the above-described state, a call control processor CSRP3 (FIG. 25) is grown to shift the control of the highway HW2 accommodated in the call control processor CSRP2 to the new call control processor CSRP3, thereby dispersing the load.
(4) Since the call control and signal control processors CSPR1 and CSPR2 do not have a floating function and the highways HW1 and HW2 are fixedly accommodated in the respective call control and signal control processors, it is necessary to temporarily stop the communication between the lines A and B in order to shift the control of the highway HW2.
5) After the call on the line B is finished, the line data on the line B and the highway HW2 are shifted to the call control and signal control processor CSPR3, and the connection of the line B is also physically changed to the call control and signal control processor CSPR3.
A similar control is executed and it is necessary to temporarily stop the communication of the subscriber in the course of talking in the case of shifting a line to the existing call control processor CSRP without growing a new processor. It is also necessary to temporarily stop the talking of the subscriber at the time of the degrowth of a call control and signal control processor.
In an exchange in use, the system sometimes changes to a new system using a new file such as a new exchange program which includes addition of a new function, modification of a function and so on. This change will be called generic update hereinunder. In such generic update, it is necessary to transfer the data in the old system to the new system. In a conventional exchange, the data in the old system are transferred into data in the new system after they are subjected to conversion/modification. In addition, priority is given to the generic update time, so that the acceptance of a request for conversion or change of each data in the old system is temporarily limited, and all the data are collectively transferred to the new system. Furthermore, data such as a call state which is frequently changed are also collectively transferred to the new system. In this manner, since the states of the old system transferred to the new system are only the states at the start point of time of data transfer and comparative long time is required until the end of transfer, the actual current states of the old system do not agree with the states of the new system after the end of transfer due to time difference. For this reason, the call is forcibly released and initialized after the end of transfer, and even the call is a stable call such as a call in the course of talking or ringing, it is not relieved.
FIG. 26 is an explanatory view of generic update in a multiprocessor exchange having no floating function. The same reference numerals are provided for the elements which are the same as those shown in FIG. 21. The subscriber (line) A is accommodated in the switch SW1 and controlled by the call control and signal control processors CSPR1, while the subscriber (line) B is accommodated in the switch SW2 and controlled by the call control and signal control processors CSPR2. If generic update (hereinunder referred to GU) is executed in this state, the line related data 1a, 1b managed by the respective line control firmwares LMF1, LMF2 and the call state data of the subscribers 2a, 2b managed by the respective call control processors CSPR1, CSPR2 are initialized, thereby the data before GU are changed into the data after GU.
It is possible to disperse the load of a call control processor in a multiprocessor exchange having no floating function. However, it is necessary to physically switch the connection of lines in order to change the load of each call control processor after the construction of a system, which work is disadvantageously troublesome.
The present inventor proposes a multiprocessor exchange provided with a floating function in order to solve the first problem. However, a multiprocessor exchange provided with a floating function cannot relieve a stable call in the same manner as in the xe2x80x9crestart processing with reliefxe2x80x9d executed by a conventional exchange having no floating function. More specifically, in the conventional multiprocessor STM exchange, when there generates an event which requires a processing including matching and relief (for example, xe2x80x9crestart processing with reliefxe2x80x9d), it is possible to relieve a stable call only by executing a simple match processing on the call control information which is fixedly placed within the extent of physical connection. In contrast, in a mutiprocessor exchange provided with a floating function, it is impossible to relieve a stable call by adopting the conventional method. This means a new method for relieving a stable call in the multiprocessor exchange provided with a floating function.
The new type of multiprocessor exchange proposed above is provided not only with a plurality of call control processors but also with a signal distribution control processor between a line controller and each of the call control processors, and a terminal apparatus inputs line allocation information for allocating a line to each call control processor. The signal distribution control processor distributes the call control information which is input from a line controller to the call control processor corresponding to the line, and distributes the call control information input from a call control processor to the corresponding line controller by reference to the line allocation information. According to such a new type of multiprocessor, (1) it is possible to disperse the load of a processor by sharing the function of call control, signal distribution control, maintenance, etc. with each other. (2) It is possible to allocate lines or highways to the corresponding call control processors by inputting the line allocation information from the terminal apparatus, which enables the dispersion of the load of a processor without the need for changing the physical line connection. In addition, (3) it is possible to provide the exchange with a floating function of a processor.
A new type of multiprocessor exchange, however, is different from a conventional multiprocessor exchange in that when there generates an event which requires a processing including matching and relief (for example, a xe2x80x9crestart processing with reliefxe2x80x9d), it is necessary to execute match and relief processing by taking the difference in function allocated to each processor and the positions of temporary data produced when a call is actually set into the consideration. This is especially the case with an exchange which has introduced an object oriented software structure, and further with an exchange adopting a pack communication system aimed at a reduction in the amount of communication between the processors. The pack communication system is a periodical communication system for collectively communicating data which have been required to communicate between processors, for example, every 16 ms. As described above, when a processor or a firmware of a new type of STM exchange needs to execute a xe2x80x9crestart processing with reliefxe2x80x9d, the match processing aimed at the relief of a stable call such as a call in the course of talking or ringing is necessary. It is also necessary to stop a call processing of only the line or the highway related to the processor on which the xe2x80x9crestart processing with reliefxe2x80x9d is executed, and not to stop a call processing of the lines or the highways related to the other processors or firmwares.
In an exchange in use, a line or a highway is sometimes shifted to a grown processor or another processor with a less load in order to disperse the load of a call processing. In a conventional exchange, lines or highways are fixed to call control processors. For this reason, it is necessary to change the physical connection of the line or the highway as the object at the time of shift, and since the lines or the highway cannot be used during this period, it is also necessary to release the stable call on the line. Accordingly, in a conventional multiprocessor exchange, it is disadvantageously impossible to relieve a stable call during shift.
Since the state of a new system after the end of transfer of the data does not agree with the actual state in a conventional generic update, the call is forcibly released and initialized immediately after the leadership of the control is swiched from the old system to the new system, and a stable call such as a call in the course of talking or ringing is not relieved. In the generic update proposed in the present invention, the old system transfers the data to a new system without stopping the use, and the new system receives the old data and starts to convert or modify the old data into new data. Even after the transfer of the old data from the old system to the new system and the conversion or modification of the old data, the old system continues to transfer the difference between the remaining old data and the data transferred to the new system. Accordingly, it is possible to transfer the latest state of the data in the old system to the new system. In this case, there is a possibility of relieving a stable call, and it is required to relieve the stable call immediately after the leadership of the control is switched from the old system to the new system.
Accordingly, it is an object of the present invention to eliminate the above-described problems in the related art and to provide a multiprocessor exchange which is able to change the load of each call control processor easily only by changing the logical line allocation information which specifies the line to be allocated to each call control processor without the need for changing the physical line connection.
It is another object of the present invention to provide a multiprocessor exchange which is able to specify lines to be allocated to each call control processor individually per line basis or collectively per highway basis, and to stop or start a call processing on a line or a highway irrespective of the other lines or highways.
It is still another object of the present invention to provide a multiprocessor exchange which enables match processing aimed at the relief of a stable call such as a call in the course of talking or ringing when one of a call control processor, a signal distribution control processor and a firmware which constitute the multiprocessor exchange having a floating function executes restart processing.
It is a further object of the present invention to provide a multiprocessor exchange provided with a floating function which is able to relieve a stable call when a line or a highway is shifted.
It is a still further object of the present invention to provide a multiprocessor exchange provided with a floating function which is able to relieve a stable call at the time of a restart processing after systems are switched for a generic update.
To achieve these objects, the present invention provides multiprocessor exchanges provided with the following functions (a) to (d).
A multiprocessor exchange having a floating function according to the present invention comprises a plurality of call control processors and a signal distribution control processor provided between a line controller and each of the call control processors, and a terminal apparatus inputs line allocation information so as to allocate a line to each of the call control processors. The signal distribution control processor distributes the call control information on a predetermined line which is input from the line controller to the call control processor corresponding to the line by reference to the line allocation information, and distributes the call control information input from the call control processor to the corresponding line controller. In this manner, it is possible to change the load of each call control processor easily only by changing the line allocation information for allocating a line to each call control processor without the need for changing the physical line connection.
In the multiprocessor exchange according to the present invention, a terminal, apparatus as a line allocating means is able to allocate lines to each control processor individually per line basis or collectively per highway basis.
In the multiprocessor exchange according to the present invention, the call control processor can also serve as a signal distribution control processor.
In the multiprocessor exchange according to the present invention, when a plurality of line controllers are provided, the signal distribution control processor is able to distribute the call control information which is to be input from a call control processor to a predetermined line to the line controller to which the line is connected.
In the multiprocessor exchange according to the present invention, when a plurality of signal distribution control processors are provided, a call control processor is able to input the call control information on a predetermined line to the line controller to which the line is connected through a predetermined signal distribution control processor.
According to the multiprocessor exchange of the present invention, it is possible to change a call control processor which executes the call processing on a line without the need for changing the physical line connection, by changing the line allocation of the terminal apparatus. This change of a call control processcor is referred to as xe2x80x9cshiftxe2x80x9d.
The call control processor of the multiprocessor exchange according to the present invention is able to relieve a stable call such as a call in the course of talking or ringing by executing a match processing in the xe2x80x9crestart processing with reliefxe2x80x9d. Similarly, the signal distribution control processor and the line firmware are able to relieve a stable call by executing a match processing in the xe2x80x9crestart processing with reliefxe2x80x9d.
In the match processing in the xe2x80x9crestart processing with reliefxe2x80x9d, (1) the call control processor requires the line controller to which the line allocated thereto is connected to stop the call control by designating the lines, (2) the line control firmware of the line controller stops the call control of the designated line, (3) the call control processor then (3-1) starts a match processing aimed at the relief of the stable call on the line allocated thereto, releases the call related data of the line which corresponds to a call other than a stable call (such a call will be referred to xe2x80x9cnonstable callxe2x80x9d herein after) in the match processing, and (3-2) produces relief information for relieving the stable call and sends the information to the line control firmware, (4) the line control firmware (4-1) releases the call related data on the lines which are not designated in the relief information, (4-2) and produces non-relief information on the lines which the line control firmware does not judge as the object of relief even if they are designated in the relief information, and sends the nonrecovery information to the call control processor, (5) the call control processor releases the call related data on the lines designated in the non-relief information, and when the match processing is finished, the call control processor requires the line control firmware to start the call control on the line which has been stopped, and (6) the line control firmware starts to the call control on the designated line. In the match processing, the call control processor requires the line control firmware to stop or start the call control of the lines individually per line basis or collectively highway basis.
In this manner, the call processing of only the line or highway which is related to the call control processor which is executing the xe2x80x9crestart processing with reliefxe2x80x9d is stopped, and the call processing of the lines or highways related to the others are not stopped. It is therefore possible to limit the number of lines which cannot be used in the match processing at the time of xe2x80x9crestart processing with reliefxe2x80x9d to the minimum, and further to shorten the matching time and therefore the time during which the line cannot be used, thereby enhancing the reliability of the system.
In the multiprocessor exchange having a floating function according to the present invention, when the line allocated to the first call control processor in the course of call processing is shifted to a second call control processor, the call control information on the line held by the first call control processor is transferred to the second call control processor, thereafter the second call control processor executes a match processing in order to relieve the stable call, and then the second call control processor starts a call control.
In the match processing, the second call control processor (1) starts a match processing aimed at the relief of the stable call on the line which is allocated to the second call control processor, releases the line related data on the lines which correspond to nonstable calls in the match processing, produces relief information for relieving a stable call and sends the information to the line control firmware, (2) the line control firmware (2-1) releases the call related data on the lines which are not designated in the relief information, and (2) produces non-relief information on the lines which the line control firmware does not judge as the object of relief even if they are designated in the relief information, and sends the non-relief information to the call control processor, and (3) the second call control processor releases the call related data on the lines designated in the non-relief information and starts a call control. In the match processing, the call control processor requires the line control firmware to stop or start the call control of lines individually per line basis or collectively per highway basis. In this manner, the second call control processor is able to relieve the stable call in the match processing after the shift, and the call processing only on the lines or highways which are allocated to the second call control processor is stopped, while the call processing on the lines or highways which are allocated to another call control processor is not stopped.
The old file held by each of a active call control processor and standby call control processor is updated into a new file, and the control is switched over from the active call control processor to the standby call processor as a new call control processor. The new call control processor starts xe2x80x9crestart processing due to the generic updatexe2x80x9d. The new call control processor relieves the stable call such as a call in the course of talking or calling by executing a match processing in a similar manner as in (b).
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings.